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<head>
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    <title>键盘事件</title>
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</head>

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        window.onload = function () {
            document.getElementById("text").addEventListener("keydown", function (event) {
                if (
                    // 表示同时按下2个及以上的键触发
                    (event.getModifierState('Control') +
                    event.getModifierState('Alt') +
                    event.getModifierState('Meta') )> 1) {
                    console.log(Date.now());
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